Background: Reporting templates are increasingly common in all fields of pathology. In this paper, we present an assessment of the impact of a thyroid fine needle aspiration cytology (FNAC) template on diagnostic classification and cytohistologic concordance. Materials and Methods: A thyroid FNAC reporting template was developed and introduced at a university teaching hospital. We examined FNAC reports for a five-month period before introduction of the template and compared these to the five month period after the template introduction. We recorded diagnostic categorization as well as cytohistologic correlation. Results: A total of 168 cases were identified in the five month period prior to the introduction of the reporting template and 172 cases in the five month period after the introduction of the reporting template. The template appeared to improve the diagnostic precision of benign conditions without altering the proportion of cases classified as unsatisfactory, benign or abnormal. There was no significant difference in the rate of cytohistologic concordance before and after the template introduction. Conclusions: The introduction of a reporting template for thyroid FNAC improved diagnostic precision of benign conditions and did not alter the general diagnostic classification or cytohistologic concordance.

Management of thyroid nodules is a common surgical problem. Fine needle aspiration cytology (FNAC) is the most sensitive, specific, and cost-effective initial investigation used to identify patients who require surgical intervention.[1] It is important, however, that the pathology report on a thyroid FNAC accurately communicate the diagnosis to the surgeon and thereby guide appropriate further management of the patient.[2],[3]

Clear reporting is significantly enhanced by reporting templates using standardized diagnostic categories. Numerous reporting formats have been developed over the past few decades,[4] including one developed by the Papanicolaou Society.[5] Universally accepted terminology, however, does not yet exist.[6]

In response to differences in reporting styles among cytopathologists which led to some dissatisfaction on the part of clinicians (FNAs were performed by clinicians only), a thyroid FNAC reporting template was developed and implemented. We hypothesized that the introduction of this template would improve communication and lead to clearer reporting of FNAC diagnosis. To test this, we informally interviewed cytopathologists, cytotechnologists and clinicians following the implementation of the template as well as recording data on the effect of this template on FNAC diagnostic categories and cytohistologic concordance.

Materials and Methods

This study was conducted at the Queen Elizabeth II Health Sciences Centre, in Halifax, Nova Scotia, Canada, which provides primary healthcare to a population of 400,000 as well as consultation services to a total of two million people.

The reporting template was developed by one of the authors (LG), following a multidisciplinary meeting of cytopathologists and cytotechnologists. Our initial draft template was based on the reporting template developed by the Papanicolaou Society.[5] For further explanation of the diagnostic categories used in the template, readers are referred to the Papanicolaou Society website.[5] The draft template was then circulated to cytopathologists, cytotechnologists, and clinicians for comment. Based on the input from these individuals, a final version of the reporting template was developed.

The final version of the reporting template included patient demographics, clinical history, specimen type, specimen adequacy, diagnostic category, and comment. Criteria for adequacy include a well-preserved specimen containing at least six groups of at least ten follicular cells each. This is the minimal requirement generally accepted in the literature. [7] Diagnostic categories included unsatisfactory, benign, abnormal, suggestive of malignancy and malignant [Table 1].

We assessed the impact of the template by comparing thyroid FNAC reports in five months before introduction of the template (January 1-May 31, 2006) with thyroid FNAC reports in the five months after the introduction of the template (June 1-October 31, 2006). Cases were identified by searching the hospital laboratory information system. Data from these reports were then abstracted into a data file.

Tissue correlation was performed in all cases where a thyroid surgical specimen was identified in the same patient within six months following the FNAC and concordance rates were determined. Clinicians, cytopathologists, and cytotechnologists were also requested to report on their satisfaction with reports.

The content validity of our reporting template can be assumed because it was based largely on a template developed by expert consensus.[5] The construct validity of the reporting template was assessed by testing the prediction that it should result in an improvement in the diagnostic precision of FNAC reports.

Results were analyzed using Chi-squared and Fisher's Exact Tests in StatView for Windows, version 4.57. Statistical comparisons were considered significant at an alpha <0.05.

Results

A total of 168 cases were identified in a five month period prior to the introduction of the reporting template and 172 cases in a five month period after the introduction of the reporting template.

When the two different five month periods were compared by general diagnostic categories, there were no statistically significant differences in the proportion of cases classified as unsatisfactory, benign or abnormal (Chi-squared test, P = 0.38). The malignant and suggestive malignancy categories were not compared statistically due to the small number of cases in these categories [Table 2].

However, within the benign category there was a marked increase in cases diagnosed as hyperplastic nodules, from 11% before the introduction of the reporting template to 22% after the introduction of the reporting template (Fisher's exact test, P = 0.0001). This was accompanied by a reduction in all of the other benign diagnostic subcategories [Table 2].

Results of the tissue correlation are summarized in [Table 3]. There were 45 and 51 cases pre and post-template which had corresponding thyroid surgical specimens within six months of the FNAC. The 11 and 13 unsatisfactory cases were excluded, leaving 34 and 38 cases on which correlation was performed. Overall concordance rates were 68% and 63% pre and post-template (Fisher's exact test, P = 0.81).

Feedback from clinicians, cytopathologists, and cytotechnologists indicated uniform satisfaction with the use of the templates and reports.

Discussion

The introduction of a thyroid FNAC reporting template appears to have had a significantly positive impact on thyroid FNAC reporting at our institution from the point of view of clinicians, cytopathologists, and cytotechnologists. The development of the template encouraged communication between clinicians, cytopathologists, and cytotechnologists, enhancing mutual understanding of the role of the FNAC in the management of thyroid lesions, and encouraging consistency in the use of diagnostic categories and terminology.

The most significant change in diagnostic categories following the introduction of the reporting template was a marked increase in the diagnosis of hyperplasic nodules, with a corresponding decrease in all of the other benign subcategories including the nondiagnostic subcategory. It appears likely that during the pre-template period, cases with features of a hyperplastic nodule were merely described without a specific diagnosis being rendered, and the use of the reporting template encouraged a specific diagnosis of hyperplastic nodule to be made. This observation suggests that the reporting template and the educational activity accompanying its introduction may have improved the precision of reporting by encouraging the rendering of specific diagnoses rather than descriptions. There was no significant change in cytohistologic concordance rates. This improvement in diagnostic precision supports the construct validity of our reporting template.

The incidence of diagnostic categories: Unsatisfactory at 34%, benign at 41%, abnormal at 24%, suggestive at 1%, and malignant at 1%, appears comparable to rates reported previously. For example, Howlett et al.,[8] reported an incidence of nondiagnostic (that most likely includes unsatisfactory cases) at 30%, benign at 51%, follicular (that most likely includes follicular and Hurthle cell neoplasms, which are included in our category of abnormal) at 17% and malignant at 3%. Cytohistologic concordance rates reported here also compare favorably with those described in the literature.[9] In conclusion, the introduction of a reporting template increased the diagnostic precision of thyroid FNAC reporting without impacting overall diagnostic categorization or cytohistologic concordance. We felt that there was an overall net benefit to the implementation of this template.

Acknowledgments

We wish to thank Dr. Rebecca MacIntosh, Darlene MacLaren, and all the members of the QEII Cytopathology Laboratory for their important contribution to the development and implementation of the thyroid FNAC reporting template.